Fennel And Onion Tart

["Preheat oven to 400 F. Coat large baking sheet with non-stick cooking spray.", "Roll out puff pastry sheets on lightly floured surface into 12"" squares. Place one sheet on baking sheet and lightly brush top with water. Place second sheet directly on top of first sheet.", "In medium bowl, combine ricotta, sour cream and salt and pepper to taste; stir until smooth.", "In large skillet, cook bacon over medium heat 5 minutes or just until it begins to brown. Using a slotted spoon, transfer bacon to paper towel-lined plate.", "Spread ricotta mixture evently over puff pastry, leaving a 1"" border. Arrange fennel, onion and bacon over ricotta. Sprinkle with Parmesan and seaon with salt and pepper to taste.", "Bake 20-25 minutes or until pastry is golden. Remove and let cool slightly. Cut into 36 pieces; top with fresh fennel fronds; serve warm."]